What is the most secure way to convert a large ammount from bitcoin to fiat? I m scared that doing it through an exchange like coinbase i could get my withdraw blocked and not get my money back to my bank account

What is OP’s time preference?

If time is of no concern, I say “Slowly. Through Bisq.” IMO that’s the most secure, because you have no idea what these exchanges are going to do. They discriminate against coins with certain history. They do random KYC blockades. They report everything about you. A large deposit will warrant a special filing with the IRS. It’s all bullshit. Do not subject yourself to that hassle.

Even with Bisq, I’d whirlpool all of it several times before exchanging. That is a more effective history eraser than swapping with other currencies, because what you get from several whirlpools has effectively NO history, different from what you get from a swap.

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